Europe is committing suicide. Or at least its leaders have decided to commit suicide. Whether the European people choose to go along with this is, naturally, another matter. When I say that Europe is in the process of killing itself, I do not mean that the burden of European Commission regulation has become overbearing or that the European Convention on Human Rights has not done enough to satisfy the demands of a particular community.

I mean that the civilisation we know as Europe is in the process of committing suicide and that neither Britain nor any other western European country can avoid that fate, because we all appear to suffer from the same symptoms and maladies.As a result, by the end of the lifespans of most people currently alive, Europe will not be Europe and the peoples of Europe will have lost the only place in the world we had to call home.

Those in power seem persuaded that it would not matter if the people and culture of Europe were lost to the world.There is no single cause of the present sickness. The culture produced by the tributaries of Judaeo-Christian culture, the ancient Greeks and Romans, and the discoveries of the Enlightenment has not been levelled by nothing. But the final act has come about because of two simultaneous concatenations — sets of linked events — from which it is now all but impossible to recover.

We know that we Europeans cannot become whatever we like. We cannot become Indian or Chinese, for instance. And yet we are expected to believe that anyone in the world can move to Europe and become European.

An equally significant question erupted at the time around the position and purpose of the nation state. From the Treaty of Westphalia in 1648 up to the late 20th century the nation state in Europe had generally been regarded not only as the best guarantor of constitutional order and liberal rights but the ultimate guarantor of peace.

Yet this certainty also eroded. European figures such as Chancellor Helmut Kohl of Germany in 1996 insisted that “The nation state . . . cannot solve the great problems of the 21st century.” Disintegration of the nation states of Europe into one large integrated political union was so important, Kohl insisted, that it was in fact “a question of war and peace in the 21st century”.

And all the time the flow into Europe continues. Over the Easter weekend alone European naval vessels collected more than 8,000 African migrants from the seas around Italy and brought them into Europe. Such a flow — which used to be unusual — is now routine, apparently unstoppable and also endless.

In The World of Yesterday, published in 1942, the Austrian writer Stefan Zweig wrote that in the years leading up to the Second World War, “I felt that Europe, in its state of derangement, had passed its own death sentence.” Only his timing was out. It would take several more decades before that death sentence was carried out — by ourselves on ourselves.